1. Field of the Invention
The invention refers to an implantable cylindrical device for connecting a hose outside of the human or animal body to a hose arranged inside the said body, wherein an anchoring plate falling away peripherally from the skin surface is arranged around the cylindrical device.
2. Description of the Related Art
U.S. Pat. No. 5,306,255 describes a subcutaneous implantable port body. A subcutaneous port body is covered completely by skin and normally remains inside the human body for several months or even years. The port body contains the port chamber. The port chamber, fully located inside the human or animal body, is sealed by a puncturable plastic membrane on the skin side, while a catheter leading to the drug release site is fixed on the side facing the interior of the body. In order to administer the drugs, the skin and membrane are punctured with a needle of an infusion set. The creates a continuous drug channel from the infusion set to the release site.
European Patent EP-B-0 302 076 describes a cylindrical, percutaneous implantable port body. In contrast to the subcutaneous port body, the percutaneous port body is not fully implanted in the human body but is fixed in the tissue in such a way that at least a certain area of the port body is not covered by skin. The center of this area contains a first aperture. A second aperture of the port body is located opposite the first aperture in the section of the port body completely surrounded by tissue. A catheter whose end is located at the site inside the body to which the drug is to be transported is connected to this aperture. The port body consists of two metal parts which are screwed together. The inside of the port body, the port chamber, contains a puncturable membrane, separating the two apertures. The external casing of the port body contains several radial grooves for laterally anchoring the port in the subcutaneous skin tissue, with the outermost groove being located directly under the surface of the skin. The port chamber is also anchored with a base plate in the tissue.
The disadvantages of the subcutaneous port are that the catheter can neither be changed nor mechanically cleaned without explanting the port. A further disadvantage is that the skin is always punctured in the same place. In the short term this is painful and in the long term this causes a perforation of the skin and membrane.
The disadvantages of the described percutaneous port are that it is very heavy and has a large visible external surface. The metal port body is furthermore easily noticeable because of its color. Installed port bodies contain a gap between the base plate and the port body which is difficult to clean and sterilize. This represents an infection hazard. The radial grooves are arranged and dimensioned in such a way that sharp edges and corners are created. In these areas an effective growing-in of the tissue cells and adequate cleaning of the surface is not possible. Due to a lack of a geometrical separating line between the skin surface and the uppermost groove, external body perspiration or dirt may directly enter the grooves. In extreme cases this may cause an infection and require the port to be explanted. A further disadvantage is that the components of the described port must be machined from solid material. The manufacturing costs are consequently high with any weight reduction measures incurring additional costs. Prior art anchorings also present the hazard that parts of the anchoring may project from the skin due to the effect of a tilting moment.